Electronic component manufacturing method and apparatus

ABSTRACT

An electronic component manufacturing method includes a blotting process of bringing a conductive paste applied to an end portion of each electronic component body held by a jig into contact with a surface of a surface plate. The blotting process includes simultaneous performance of a distance changing process of changing the distance between an end face of each electronic component body and the surface of the surface plate and a position changing process of changing a two-dimensional position where the end face of the electronic component body is projected on the surface of the surface plate in such a manner that the direction of the movement of two-dimensional position in parallel to the surface of the surface plate successively varies (e.g., along a circular path).

This application is based upon and claims the benefit of priority toJapanese Patent Application No. 2018-130961, filed on Jul. 10, 2018, andJapanese Patent Application No. 2018-168952, filed on Sep. 10, 2018, theentire contents of which are incorporated herein by reference.

BACKGROUND

The present disclosure relates to an electronic component manufacturingmethod and an electronic component manufacturing apparatus.

The present inventors have proposed an apparatus and method for formingan external electrode on an electronic component body, such as alaminated ceramic capacitor, an inductor, or a thermistor, by dipcoating a conductive paste layer on an end face of this electroniccomponent body (JP-A-2002-237403). The film thickness of the conductivepaste layer as it is dip-coated cannot be made uniform. Therefore, it isconventionally proposed to pull up an electronic component bodydip-coated with the conductive paste from a conductive paste film layerformed on a surface plate and then bring a saggy portion of theconductive paste formed on an end portion of the electronic componentbody into contact with the surface plate from which the conductive pastefilm layer has been removed (JP-A-63-45813). This process is referred toas a blotting process because extra conductive paste on the electroniccomponent body is wiped off by the surface plate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating, as an embodiment of the disclosure, anexemplary electronic component manufactured by an electronic componentmanufacturing apparatus according to an electronic componentmanufacturing method:

FIG. 2 is a cross-sectional view illustrating the electronic componentillustrated in FIG. 1:

FIG. 3 is a diagram illustrating an electronic component manufacturingapparatus according to an embodiment of the disclosure;

FIG. 4 is a block diagram illustrating the manufacturing apparatusillustrated in FIG. 3;

FIGS. 5A and 5B are diagrams illustrating an exemplary blotting processto be performed by the manufacturing apparatus illustrated in FIGS. 3and 4;

FIGS. 6A to 6D are diagrams illustrating, as a first embodiment of thedisclosure, operations in the blotting process illustrated in FIG. 5A;

FIGS. 7A to 7D are diagrams illustrating, as the first embodiment of thedisclosure, operations in the blotting process illustrated in FIG. 5B;

FIGS. 8A to 8D are diagrams illustrating, as a comparative example,operations in a blotting process in which no distance changing processis included;

FIG. 9 is a cross-sectional view illustrating an electronic componentbody manufactured by performing the blotting process illustrated in FIG.5A or FIG. 5B:

FIG. 10 is a diagram illustrating a coating process according to a thirdembodiment of the disclosure to be performed by the manufacturingapparatus illustrated in FIGS. 3 and 4:

FIG. 11 is a diagram illustrating a coating process in a comparativeexample;

FIG. 12 is a diagram illustrating the state of conductive paste atrespective descent positions during the blotting process according tothe third embodiment of the disclosure illustrated in FIG. 5B; and

FIG. 13 is a diagram illustrating data obtained by evaluating blottingprocesses of the present embodiment and two comparative examples.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following disclosure provides many different embodiments, orexamples, for implementing different features of the provided subjectmatter. These are, of course, merely examples and are not intended to belimiting. In addition, the disclosure may repeat reference numeralsand/or letters in the various examples. This repetition is for thepurpose of simplicity and clarity and does not in itself dictate arelationship between the various embodiments and/or configurationsdiscussed. Further, when a first element is described as being“connected” or “coupled” to a second element, such description includesembodiments in which the first and second elements are directlyconnected or coupled to each other, and also includes embodiments inwhich the first and second elements are indirectly connected or coupledto each other with one or more other intervening elements in between.Further, when the first element is described as “moving” relative to thesecond element, such description includes embodiments in which at leastone of the first element and the second element moves relative to theother.

The disclosure intends to provide an electronic component manufacturingmethod and an electronic component manufacturing apparatus, in which theblotting process is further improved, based on intensive studies on thecause of non-uniform conductive paste layers formed on ends ofelectronic component bodies.

(1) According to one aspect of the disclosure, there is provided anelectronic component manufacturing method comprising:

blotting of bringing a conductive paste applied to an end portionincluding an end face of an electronic component body held by a jig intocontact with a surface of a surface plate, thereby transferring extraconductive paste to the surface plate,

the blotting including simultaneous performance of:

distance changing of changing a distance between the end face of theelectronic component body and the surface of the surface plate, and

position changing of changing a two-dimensional position where the endface of the electronic component body is projected on the surface of thesurface plate in such a manner that the movement direction of thetwo-dimensional position successively varies in a plane parallel to thesurface of the surface plate.

According to the aspect (1) of the disclosure, by implementing theposition changing, the movement direction of the electronic componentbody relative to the surface plate successively varies in the planeparallel to the surface plate. Here, although the extra conductive pasteon the electronic component body is dragged by the surface plate or theconductive paste transferred to the surface plate, the extra conductivepaste is easily scraped off since the direction of dragging successivelyvaries. Further, the aspect (1) of the disclosure does not cause aproblem such that the extra conductive paste stays downstream in themovement direction, as in the case of linear movement in which therelative movement direction does not successively vary, and the filmthickness of the conductive paste layer is locally thickened. Further,when the end face of the electronic component body is rectangular, theextra conductive paste is easily collected at the corner portion and itbecomes easy to secure the film thickness of the conductive paste at thecorner portion. In addition, implementation of the distance changing canadjust the amount of the conductive paste to be brought into contactwith the surface plate during the blotting. Therefore, depending on thefilm thickness of the conductive paste to be secured for the electroniccomponent body, the film thickness can be selectively adjusted byshortening or extending the distance in the distance changing. Thisblotting is such that the extra conductive paste is scraped off duringthe blotting including the distance changing and the position changing,and the conductive paste does not draw threads after the blotting.

The blotting may be performed simultaneously for a plurality ofelectronic component bodies held by a jig. Further, the blotting may beperformed after applying a conductive paste in advance on the surface ofthe surface plate to form a wet layer of the conductive paste on thesurface of the surface plate. In this case, in the blotting, the extraconductive paste on the electronic component body is brought intocontact with the wet layer formed on the surface of the surface plate.The extra conductive paste of the electronic component body is easilytransferred to the wet layer of the same conductive paste layer ratherthan a dry surface of the surface plate mainly formed of metal.

(2) In the aspect (1) of the disclosure, in the position changing, themovement locus of the two-dimensional position draws a loop, and in theblotting, the electronic component body can be spirally moved relativeto the surface of the surface plate. As a result, while minimizing therequired area of the surface plate, the position changing can beefficiently implemented.

(3) In the aspect (1) or (2) of the disclosure, the distance changingcan extend the distance between the end face of the electronic componentbody and the surface of the surface plate. In this case, the electroniccomponent body relatively moves in a direction away from the surfaceplate during the blotting. Therefore, the amount of the conductive pastetransferred to the surface plate is reduced, and a relatively thick filmthickness of the conductive paste of the electronic component body canbe secured.

(4) In the aspect (1) or (2) of the disclosure, the distance changingcan shorten the distance between the end face of the electroniccomponent body and the surface of the surface plate. In this case, theelectronic component body relatively moves in a direction approachingthe surface plate during the blotting. Therefore, the amount of theconductive paste transferred to the surface plate is increased, and arelatively thin film thickness of the conductive paste of the electroniccomponent body can be secured. Further, the distance changing may extendthe distance between the end face of the electronic component body andthe surface of the surface plate after shortening the distance betweenthe end face of the electronic component body and the surface of thesurface plate.

(5) Another aspect of the disclosure relates to an electronic componentmanufacturing method including blotting of bringing a conductive pasteapplied to an end portion including an end face of each of a pluralityof electronic component bodies held by a jig into contact with a surfaceof a surface plate. In the blotting, a height changing of shortening thedistance between the end face of each the plurality of electroniccomponent bodies and the surface of the surface plate and a positionchanging of changing a two-dimensional position where the end face ofeach of the plurality of electronic component bodies is projected on thesurface of the surface plate at different heights set by the heightchanging are performed by causing the jig and the surface plate torelatively move.

According to the aspect (5) of the disclosure, the plurality ofelectronic component bodies are relatively moved to approach the surfaceplate during the height changing and the plurality of electroniccomponent bodies are relatively moved in a direction parallel to thesurface plate during the position changing. Here, the positions of theend faces of the plurality of electronic component bodies held by thejig may vary. In this case, if the height changing is not performed, theblotting is performed while maintaining the height position of the jigwith respect to the surface of the surface plate. In this case, theblotting is performed in a state where electronic component bodiesshorter in distance from the surface of the surface plate to the endface and electronic component bodies longer in distance from the surfaceof the surface plate to the end face are mixed. This impedes theuniformity of the shape of the conductive paste layer applied to the endportions of the plurality of electronic component bodies. Theimplementation of the position changing at different heights set by theheight changing according to another aspect of the disclosure canequalize the conductive paste layers formed on the end faces of theplurality of electronic component bodies to have a required thicknessregardless of variation in position of the end faces of the plurality ofelectronic component bodies. As a result, the conductive paste layersformed on the end portions of the plurality of electronic componentbodies are made uniform in shape.

(6) In another aspect (5) of the disclosure, the blotting can includesimultaneous performance of the height changing and the positionchanging. In this case, while the plurality of electronic componentbodies relatively move closer to the surface plate, the plurality ofelectronic component bodies are relatively moved with the component inthe direction parallel to the surface plate. As a result, the conductivepaste layers are made uniform in thickness even when the positions ofthe end faces of the plurality of electronic component bodies held bythe jig are irregular in variation amount.

(7) In another aspect (6) of the disclosure, the height changing and theposition changing to be simultaneously performed can cause the pluralityof electronic component bodies to relatively approach the surface of thesurface plate while moving spirally. As a result, the position changingcan be efficiently implemented while minimizing the required area of thesurface plate. Further, during the blotting, the relative movementdirection of the electronic component body with respect to the surfaceplate successively varies in the plane parallel to the surface plate. Asa result, the surface plate or the conductive paste transferred to thesurface plate drags the conductive paste from the electronic componentbody, and the extra conductive paste can be transferred from theelectronic component body to the surface plate.

(8) Another aspect of the disclosure relates to an electronic componentmanufacturing method including coating of applying the conductive pasteto an end portion of each of the plurality of electronic componentbodies held by the jig by bringing the end portion including the endface of each of the plurality of electronic component bodies intocontact with a dip layer of the conductive paste formed on the surfaceof a first surface plate, wherein the coating includes bringing the endface of each of the plurality of electronic component bodies intocontact with the surface of the first surface plate by causing relativemovement of the jig and the first surface plate, the jig elasticallyholding the plurality of electronic component bodies so as to be movablein a direction perpendicular to the surface of the first surface plate.

According to the aspect (8) of the disclosure, the relative movement ofthe jig elastically holding the plurality of electronic component bodiesand the first surface plate brings the end face of each of the pluralityof electronic component bodies into contact with the surface of thefirst surface plate. Here, even in a case where the positions of the endfaces of the plurality of electronic component bodies held by the jigvary, the jig elastically holding the electronic component body causesthe electronic component body having first come in contact with thesurface of the first surface plate to retract in the directionperpendicular to the surface of the first surface plate. In this case,all the end faces of the electronic component bodies can contact thesurface of the first surface plate. As a result, in all the electroniccomponent bodies, the coating length of the conductive paste on the sidesurface rising from the end face can be equalized. Thus, the conductivepaste layers formed on the end portions of the electronic componentbodies can be made uniform in shape.

(9) Further, in the aspect (8) of the disclosure, after the coatingusing the first surface plate, the blotting according to the aspect (5)of the disclosure using a second surface plate can be performed. As aresult, the conductive paste layers formed on the end faces of theelectronic component bodies are made uniform in thickness.

(10) In another aspect (9) of the disclosure, the first surface platefrom which the dip layer formed on the surface has been removed can bealso used as the second surface plate. As a result, the apparatusimplementing this manufacturing method can be miniaturized.

(11) Another aspect of the disclosure relates to an electronic componentmanufacturing apparatus that includes a jig for holding an electroniccomponent body, a surface plate, moving means that moves the jig and thesurface plate relatively in a direction perpendicular to a surface ofthe surface plate as well as in a direction parallel to the surface ofthe surface plate, and control means that controls the moving means tobring a conductive paste applied to an end portion including an end faceof the electronic component body held by the jig into contact with thesurface of the surface plate, thereby performing a blotting operationfor transferring extra conductive paste to the surface plate. Thecontrol means causes the moving means to simultaneously perform adistance changing movement for changing the distance between the endface of the electronic component body and the surface of the surfaceplate and a position changing movement for changing a two-dimensionalposition where the end face of the electronic component body isprojected on the surface of the surface plate in such a manner that themovement direction of the two-dimensional position successively variesin a plane parallel to the surface of the surface plate.

According to the aspect (11) of the disclosure, the electronic componentmanufacturing method according to the aspect (1) of the disclosure canbe preferably implemented.

(12) Another aspect of the disclosure relates to an electronic componentmanufacturing apparatus that has a jig for holding a plurality ofelectronic component bodies, a surface plate, moving means that movesthe jig and the surface plate relatively in a direction perpendicular toa surface of the surface plate as well in a direction parallel to thesurface of the surface plate, and control means that controls the movingmeans to perform a blotting operation for bringing a conductive pasteapplied to an end portion including an end face of each of the pluralityof electronic component bodies held by the jig into contact with thesurface of the surface plate. The control means performs a height changeoperation for shortening the distance between the end face of each ofthe plurality of electronic component bodies and the surface of thesurface plate and a position change operation for changing atwo-dimensional position where the end face of each of the plurality ofelectronic component bodies is projected on the surface of the surfaceplate, by controlling the jig and the surface plate to move relatively.

According to the aspect (12) of the disclosure, the electronic componentmanufacturing method according to the aspect (5) of the disclosure canbe preferably implemented.

(13) Another aspect of the disclosure relates to an electronic componentmanufacturing apparatus that includes a jig for holding a plurality ofelectronic component bodies, a surface plate, moving means that move thejig and the surface plate relatively in a direction perpendicular to asurface of the surface plate as well as in a direction parallel to thesurface of the surface plate, and control means that controls the movingmeans to perform a coating operation for applying a conductive paste toan end portion of each of the plurality of electronic component bodiesby bringing the end portion including the end face of each of theplurality of electronic component bodies held by the jig into contactwith a dip layer of the conductive paste formed on the surface of thesurface plate. The jig elastically holds the plurality of electroniccomponent bodies so as to be movable in a direction perpendicular to thesurface of the surface plate. The control means causes the jig and thesurface plate to move relatively, thereby bringing the end face of eachof the plurality of electronic component bodies into contact with thesurface of the surface plate.

According to the aspect (13) of the disclosure, the electronic componentmanufacturing method according to the aspect (8) of the disclosure canbe preferably implemented.

(14) In the aspect (13) of the disclosure, after the coating operation,the control means can perform a height change operation for shorteningthe distance between the end face of each of the plurality of electroniccomponent bodies and the surface of the surface plate from which the diplayer has been removed and a position change operation for changing atwo-dimensional position where the end face of each of the plurality ofelectronic component bodies is projected on the surface of the surfaceplate by controlling the jig and the surface plate to move relatively,thereby performing the blotting operation for bringing the conductivepaste applied to the end portion of each of the plurality of electroniccomponent bodies held by the jig into contact with the surface of thesurface plate.

According to the aspect (14) of the disclosure, the electronic componentmanufacturing methods according to the aspects (9) and (10) of thedisclosure can be preferably implemented.

Exemplary embodiments are described below. Note that the followingexemplary embodiments do not in any way limit the scope of the contentdefined by the claims laid out herein. Note also that all of theelements described in the present embodiment should not necessarily betaken as essential elements.

1. Electronic Component

FIG. 1 illustrates an electronic component 1A manufactured according toa manufacturing method according to an embodiment of the disclosure.FIG. 2 illustrates a cross section of a conductive layer 4A formed on anelectronic component body 1. Here, the electronic component 1A to whichthe disclosure is applied is not particularly limited in size, but it isdesired that the electronic component 1A is microminiaturized accordingto downsizing. As illustrated in FIG. 1, the microminiaturizedelectronic component 1A is rectangular (square or oblong) in crosssection. When L1 represents the maximum length of one side of therectangular cross section and L2 represents the length in a directionorthogonal to the rectangular cross section, L1 is 500 μm or less and L2is 1000 μm or less. Preferably, L1 is 300 μm or less and L2 is 600 μm orless, and more preferably, L1 is 200 μm or less and L2 is 400 μm orless. Further preferably, L1 is 125 μm or less and L2 is 250 μm or less.The term “rectangle” as used herein includes not only the one in which acorner where two sides intersect is strictly 90° but also substantiallyrectangular shape in which a corner curved or chamfered. It is needlessto say that the disclosure can also be applied to any other electroniccomponent 1A that has a cross section of non-rectangular.

As illustrated in FIG. 2, at each end portion of the electroniccomponent body 1, an electrode 4A being a conductive paste layer isformed on the electronic component 1A. Each end portion 2 of theelectronic component body 1 includes an end face 2A, an end face 2B, anda corner portion 2C connecting the end face 2A and the end face 2B.Substantially uniform thickness T1 of the electrode 4A formed on the endface 2A and substantially uniform thickness T2 of the electrode 4Aformed on the end face 2B can be substantially in a relationship ofT1=T2. In addition, thickness T3 of the electrode 4A formed on thecorner portion 2C can satisfy a relationship T3≥T1 or T3≥T2. Further, L3represents the electrode length of the electrode 4A formed on the endface 2B extending from the end face 2A. A plurality of electroniccomponents 1A, when manufactured according to the manufacturing methodaccording to an embodiment of the disclosure, is required to haveuniformity in dimensions (T1 to T3 and L3) of the electrode 4A.

2. Electronic Component Manufacturing Apparatus

FIG. 3 illustrates a manufacturing apparatus 10 that can be used toimplement the present embodiment. FIG. 4 is a block diagram illustratinga control system. The manufacturing apparatus 10 has a carrier plate(jig) 20, a transfer mechanism 50, and a surface plate 100. In FIG. 3,X, Y, and Z represent three orthogonal axial directions.

The carrier plate (jig) 20, which hangs and holds the electroniccomponent bodies 1, elastically holds the electronic component bodies 1so as to be movable in a direction perpendicular to a surface 101 of thesurface plate 100. The carrier plate 20 can be configured, for example,by an adhesive tape that is elastically deformable in the Z direction.The carrier plate 20 is detachably supported by a jig fixing plate 30. Abase 40 is fixed above the jig fixing plate 30, and the surface plate100 is disposed below the jig fixing plate 30.

The surface plate 100 is provided with a squeegee unit 110 including asqueegee 112 and a blade 114. The squeegee unit 110 is movable on thesurface plate 100. By moving the blade 114, the squeegee unit 110 canform a dip layer of a conductive paste 120 having height H on thesurface 101 of the surface plate 100. By moving the squeegee 112, thesqueegee unit 110 can scrape the dip layer of the conductive paste 120from the surface 101 of the surface plate 100.

The base 40 is provided with the transfer mechanism 50 for moving thejig fixing plate 30. In the present embodiment, the transfer mechanism50 can include an X-axis driving part 60, a Y-axis driving part 70, anda Z-axis driving part 80. The transfer mechanism 50 is not particularlylimited if it can cause a relative movement between the jig fixing plate30 and the surface plate 100 in the X-, Y-, and Z-axis directions. Thatis, the transfer mechanism 50 may be configured to move the surfaceplate 100. Alternatively, the transfer mechanism 50 may be configured toinclude not only the transfer mechanism for moving the jig fixing plate30 but also another transfer mechanism for moving the surface plate 100.Alternatively, the transfer mechanism 50 may be configured such that atleast one of the X-axis driving part 60, the Y-axis driving part 70, andthe Z-axis driving part 80 causes the jig fixing plate 30 to move andthe rest causes the surface plate 100 to move.

The X-axis driving part 60 can be configured by an X table movable inthe X-axis direction with respect to the base 40 along an X-axis guide62. The Y-axis driving part 70 can be configured by a Y table movable inthe Y-axis direction with respect to the X-axis driving part 60 along aY-axis guide 72. The Z-axis driving part 80 is fixed to, for example,the Y-axis driving part 70, and can move a Z shaft 82 in the Z-axisdirection. The jig fixing plate 30 is fixed to the Z shaft 82. FIG. 3does not include any illustration of X-, Y-, and Z-axis driving sources,such as motors, and driving force transmission mechanisms thereof.

Thus, the transfer mechanism 50 enables the jig fixing plate 30, thecarrier plate 20, and the electronic component bodies 1 to move relativeto the surface plate 100 not only in the Z-axis direction but also alongan X-Y plane parallel to the surface of the surface plate 100.

As illustrated in FIG. 4, the manufacturing apparatus 10 has acontroller 90 that controls the X-axis driving part 60, the Y-axisdriving part 70, and the Z-axis driving part 80. The controller 90 isconnected to an operation input unit 92 such as a keyboard or the like.The controller 90 includes a storage unit 91. The storage unit 91 storesoperational information input via the operation input unit 92, programsregistered in advance, and the like. The controller 90 controls theX-axis driving part 60, the Y-axis driving part 70, and the Z-axisdriving part 80 according to data and programs stored in the storageunit 91. By using the X-axis driving part 60 and the Y-axis driving part70, the controller 90 can cause the jig fixing plate 30 to move along,for example, a circular path in a plane parallel to the surface plate100. Further, while the jig fixing plate 30 is moved along the circularpath by the X-axis driving part 60 and the Y-axis driving part 70, thecontroller 90 can drive the Z-axis driving part 80 to raise or lower thejig fixing plate 30.

3. Electronic Component Manufacturing Method

The manufacturing apparatus 10 according to the present embodimentperforms a coating process and subsequently performs a blotting process.The coating process is bringing the end portion 2 including the end face2A of each of the electronic component bodies 1 held by the carrierplate 20 into contact with the dip layer of the conductive paste formedon the surface 101 of the surface plate 100 to coat the end portion 2 ofeach electronic component body 1 with the conductive paste. The blottingprocess is bringing the conductive paste applied to the end portion 2 ofeach of the electronic component bodies 1 held by the carrier plate 20into contact with the surface 101 of the surface plate 100 to transferextra conductive paste to the surface plate 100.

3.1. First Embodiment

FIG. 5A schematically illustrates a blotting process according to afirst embodiment. FIG. 5A illustrates an example of relative movement ofthe surface plate 100 and the electronic component bodies 1 (althoughonly one is illustrated in FIG. 5) held by the carrier plate 20 in theblotting process. In this blotting process, to implement a distancechanging process for extending the distance between end face 2A of theelectronic component body 1 and the surface 101 of the surface plate 100and a position changing process for changing a two-dimensional positionwhere the end face 2A of the electronic component body 1 is projected onthe surface 101 of the surface plate 100 in such a manner that themovement direction of the two-dimensional position successively variesin a plane parallel to the surface 101 of the surface plate 100, thecontroller 90 controls the transfer mechanism 50 to cause the carrierplate 20 and the surface plate 100 to move relatively. That is, aprojection of the end face 2A on the surface 101 moves its projectedtwo-dimensional position on the surface 101.

FIG. 5A illustrates a spiral motion that is an example of the distancechanging process and the position changing process. That is, thecontroller 90 simultaneously controls the X-axis driving part 60, theY-axis driving part 70, and the Z-axis driving part 80 to raise theelectronic component body 1 away from the surface plate 100 whilecausing the electronic component body 1 to turn in a loop orbit, such asa circle or an ellipse. FIG. 5A illustrates positions A to D duringascent of the electronic component body 1. In FIG. 5A, similar in FIGS.5B and 12, the conductive paste layer formed at the end portion 2 of theelectronic component body 1 is indicated by reference numeral 4 if theblotting process is not completed yet and by reference numeral 4A afterthe completion of the blotting process. Further, the conductive pastetransferred to the surface plate 100 is denoted by reference numeral 4B.

FIGS. 6A to 6D illustrate blotting operations at respective positions Ato D illustrated in FIG. 5A. In FIG. 6A, of the conductive paste layer 4formed at the end portion of the electronic component body 1, the extraconductive paste 4B having been brought into contact with the surfaceplate 100 is transferred to the surface plate 100 while it is draggedtoward the downstream side in a horizontal movement direction of theelectronic component body 1, as illustrated in FIGS. 6B and 6C. At thistime, while the position changing process is performed, the relativemovement direction of the electronic component body 1 with respect tothe surface plate 100 successively varies in the plane parallel to thesurface plate 100. Although the conductive paste layer 4 of theelectronic component body 1 is dragged by the conductive paste 4Btransferred to the surface plate 100 or the surface plate 100, theconductive paste layer 4 is easily scraped off since the direction ofdragging successively varies. In addition, the problem such that theextra conductive paste stays downstream in the movement direction doesnot occur as in the case of linear movement in which the relativemovement direction does not successively vary. Therefore, the filmthickness of the conductive paste layer 4A is not locally thickened.Further, when the end face 2A of the electronic component body 1 isrectangular, the extra conductive paste is easily collected at thecorner portion 2C, and it becomes easy to secure the film thickness ofthe conductive paste at the corner portion 2C.

In the distance changing process according to the first embodiment, theelectronic component body 1 relatively moves in a direction away fromthe surface plate 100 during the blotting process. Therefore, the amountof the conductive paste transferred to the surface plate 100 is reduced,and a relatively thick film thickness of the conductive paste of theelectronic component body 1 can be secured.

3.2. Second Embodiment

FIG. 5B schematically illustrates a blotting process according to asecond embodiment. FIG. 5B is different from FIG. 5A only in that thedistance change direction is the downward direction. That is, thecontroller 90 simultaneously controls the X-axis driving part 60, theY-axis driving part 70, and the Z-axis driving part 80 to lower theelectronic component body 1 in such a way as to approach the surfaceplate 100 while spirally turning. FIG. 5B illustrates respectivepositions A to D during descent of the electronic component body 1.

FIGS. 7A to 7D illustrate blotting operations at respective positions Ato D illustrated in FIG. 5B. Even in the second embodiment, the positionchanging process is performed in the same manner as in the firstembodiment. In a distance changing process according to the secondembodiment, the electronic component body 1 relatively moves in adirection approaching the surface plate 100 during the blotting process.Therefore, the amount of the conductive paste transferred to the surfaceplate 100 is increased, and a relatively thin film thickness of theconductive paste of the electronic component body 1 can be secured.

According to the first and second embodiments described above,implementation of the distance changing process can adjust the amount ofthe conductive paste to be brought into contact with the surface plate100 during the blotting process. Therefore, depending on the filmthickness of the conductive paste to be secured for the electroniccomponent body 1, the film thickness can be selectively adjusted byshortening (the first embodiment) or extending (the second embodiment)the distance in the distance changing process. This blotting process issuch that the extra conductive paste is scraped off during the blottingprocess including the distance and position changing processes, and theconductive paste does not draw threads after the blotting process.Accordingly, since no trace of threads is left, the surface of theconductive paste layer 4A of the electronic component body 1 becomesflat.

In the position changing processes in the first and second embodiments,not only the loop locus such as a circular path, an elliptic path, orthe like but also starting and end points of the position changingprocess in the plane parallel to the surface plate 100 do notnecessarily coincide if the direction of the relative movement betweenthe electronic component body 1 and the surface plate 100 successivelyvaries in the plane parallel to the surface plate 100.

In addition, the blotting processes of the first and second embodimentsillustrated in FIGS. 5A and 5B may be implemented in combination. First,each process according to the second embodiment illustrated in FIGS. 7A,7B, and 7C is implemented. Before the state illustrated in FIG. 7D isobtained, the distance shortening process is stopped. Subsequently, eachprocess according to the first embodiment illustrated in FIGS. 6B, 6C,and 6D is implemented to complete the blotting process. At this time,turn direction in the process illustrated in FIGS. 7A, 7B, and 7C andthe turn direction in the process illustrated in FIGS. 6B, 6C, and 6Dmay be the same or opposite. When the blot process of FIGS. 5A and 5B isperformed in combination, the thickness of the conductive paste layer 4Ais different from the thickness of the conductive paste layer 4Aobtained in the blot process of FIG. 5A or FIG. 5B. Accordingly, thefreedom degree of the thickness of the conductive paste layer 4Aspreads.

FIG. 8 illustrates a blotting process in a comparative example, in whichextra conductive paste 4C is transferred to the surface plate 10) byimplementing only the position changing process without implementing thedistance changing process, while the electronic component body 1 and thesurface plate 100 are kept constant in position in the verticaldirection. In the blotting process illustrated in FIG. 8, the operationsillustrated in FIGS. 6 and 7 cannot be performed. However, for example,if the conductive paste 4 applied to the electronic component body 1leaves sharp protrusions, the blotting process illustrated in FIG. 8 issuitable for leveling the protrusions and shaping the surface of theconductive paste 4 into a flat shape.

FIG. 9 illustrates a cross-sectional view of the electronic componentbody 1 obtained by implementing the blotting processes according to thefirst and second embodiments. As illustrated in FIG. 9, the conductivepaste layer 4A formed on the electronic component body 1 has a uniformfilm thickness on four end faces 2B continuous from the end face 2A, andthe necessary film thickness of the conductive paste layer 4A can besecured at the corner portion 2C.

3.3. Third Embodiment

A third embodiment uses the blotting process according to the secondembodiment to simultaneously perform blotting process on the electroniccomponent bodies 1.

3.3.1. Coating Process

FIG. 10 illustrates a coating process according to present embodiment.In the coating process, as illustrated in FIG. 10, a dip layer 121 ofthe conductive paste 120 (FIG. 3) is formed in advance on the surface101 of the surface plate 100. Subsequently, the controller 90 controlsthe transfer mechanism 50 to relatively move the carrier plate 20 andthe surface plate 100 in the Z direction, to bring the end face 2A ofeach of the electronic component bodies 1 into contact with the surface101 of the surface plate 100. In the example illustrated in FIG. 10, aright electronic component body 1 a is longer by h than a leftelectronic component body 1 b. The variation h of the length of theelectronic component body 1 is, for example, several tens of μm. Even inthis case, the movement in the Z direction is continued after the endface 2A of the electronic component body 1 a on the right side of FIG.10 is brought into contact with the surface 101 of the surface plate100. Therefore, the electronic component body 1 a on the right side ofFIG. 10 retracts upward due to elastic deformation of the carrier plate20, while maintaining contact with the surface 101 of the surface plate100. Then, the relative movement in the Z direction is continued untilthe end face 2A of the electronic component body 1 b on the left side ofFIG. 10 contacts the surface 101 of the surface plate 100. At this time,the carrier plate 20 and the surface plate 100 may be relatively movedin the Z direction by an over stroke amount by which the electroniccomponent body 1 b on the left side of FIG. 10 retracts upward due tothe elastic deformation of the carrier plate 20 while maintaining thecontact with the surface 101 of the surface plate 100. By bring the endface 2A of each of the plurality of electronic component bodies 1 a and1 b into contact with the surface 101 of the surface plate 100 asillustrated in FIG. 10, the length of the coating formed on the endportion 2 of each of the plurality of electronic component bodies 1 aand 1 b coincides with the height H of the dip layer 121. As a result,the lengths L3 (FIG. 2) of the electrodes 4A formed on the end portion 2of each of the electronic component bodies 1 are equalized, and theelectrodes 4A become uniform in shape.

FIG. 11 illustrates a coating process in a comparative example. Unlikethe carrier plate 20 illustrated in FIG. 10, a carrier plate 21illustrated in FIG. 11 does not have a function of holding theelectronic component body 1 so as to be elastically movable in the Zdirection. In this case, the relative movement in the Z direction isstopped when the electronic component body 1 a on the right side of FIG.11 contacts the surface 101 of the surface plate 100. Therefore, theelectronic component body 1 b on the left of FIG. 11 is not in contactwith the surface 101 of the surface plate 100, and the coating length ofthe electrode 4A formed on the end portion 2 becomes HI (<H). Therefore,coating lengths of the electrodes 4A formed on the end portions 2between the electronic component bodies 1 become irregular. According tothe embodiments of the disclosure, it is possible to prevent thevariation in coating length of the electrode 4A illustrated in FIG. 11.

3.3.2. Blotting Process

In this third embodiment, the blotting process according to the secondembodiment illustrated in FIG. 5B is employed. FIG. 12 illustrates thestate of two electronic component bodies 1 a and 1 b different inlength, during descent, at respective positions A to D illustrated inFIG. 5B. In FIG. 12, like in FIG. 10, the right electronic componentbody 1 a is longer than the left electronic component body 1 b.

At the position A in FIG. 5B, the conductive paste layers 4 of theelectronic component bodies 1 a and 1 b do not reach the surface 101 ofthe surface plate 100, as illustrated in FIG. 12. At the position B inFIG. 5B where the height changing process has been performed, theconductive paste layer 4 of the electronic component body 1 a reachesthe surface 101 of the surface plate 100, as illustrated in FIG. 12.Subsequently, as the electronic component body 1 a descends spirally,the conductive paste layer 4 contacts the surface 101 of the surfaceplate 100 while changing its position. As a result, the extra conductivepaste is scraped off to the surface plate 100, and the conductive pastelayer 4 remaining on the electronic component body 1 a is shaped whileforming threads with the conductive paste transferred to the surfaceplate 100. At the position C in FIG. 5B, the formation of threads by theelectronic component body 1 a terminates and the conductive paste layer4A is left as a completion form of the blotting process, as illustratedin FIG. 12.

On the other hand, at the position C in FIG. 5B where the heightchanging process is further performed, as illustrated in FIG. 12, theconductive paste layer 4 of the electronic component body 1 b reachesthe surface 101 of the surface plate 100. Subsequently, as theelectronic component body 1 b descends spirally, the conductive pastelayer 4 contacts the surface 101 of the surface plate 100 whilesuccessively changing its position. As a result, the extra conductivepaste is scraped off to the surface plate 100, and the conductive pastelayer 4 remaining on the electronic component body 1 b is shaped whileforming threads with the conductive paste transferred to the surfaceplate 100. At the position D in FIG. 5B, the formation of threads by theelectronic component body 1 b terminates and the conductive paste layer4A is left as a completion form of the blotting process, as illustratedin in FIG. 12.

As described above, the implementation of the blotting process accordingto the present embodiment can equalize the thicknesses of the conductivepaste layers 4A formed on end faces of the plurality of electroniccomponent bodies 1 a and 1 b even when the plurality of electroniccomponent bodies 1 a and 1 b vary in position of the end face 2A. As aresult, the conductive paste layers 4A formed on the end portions 2 ofthe plurality of electronic component bodies 1 a and 1 b are madeuniform in shape. Further, in this blotting process, the height changingprocess and the position changing process are simultaneously performed.By doing this, while the plurality of electronic component bodies 1 aand 1 b relatively move closer to the surface plate 100, the pluralityof electronic component bodies 1 a and 1 b are relatively moved with thecomponent in a direction parallel to the surface plate 100. Further,causing the plurality of electronic component bodies 1 a and 1 b to moverelatively and spirally so as to approach the surface 101 of the surfaceplate 100 can efficiently implement the position changing process whileminimizing the required area of the surface plate 100.

Although the present embodiments have been described in detail asmentioned above, it should be understood by those skilled in the artthat many modifications can be made without departing substantially fromthe new matters and effects of the disclosure. Accordingly, all suchmodifications are intended to be included in the range of thedisclosure.

For example, in the third embodiment of the disclosure, only one of thecoating process illustrated in FIG. 10 and the blotting processillustrated in FIGS. 5B and 12 may be implemented. Through the coatingprocess illustrated in FIG. 10, the length L3 (FIG. 2) of the coatingformed on the end portion 2 of each of the plurality of electroniccomponent bodies 1 a and 1 b coincides with the height H of the diplayer 121. Further, by implementing the blotting process illustrated inFIGS. 5B and 12, the thicknesses T1 (FIG. 2) of the conductive pastelayers 4A formed on the end faces of the plurality of electroniccomponent bodies 1 a and 1 b are made uniform. This is because theelectrode 4A formed on the end portion 2 of each of the electroniccomponent bodies 1 is independently made uniform in shape.

FIG. 13 illustrates representative evaluation data obtained byimplementing the blotting processes in comparative examples 1 and 2 andthe present embodiment for the electronic component bodies 1 a and 1 bdifferent in length. The comparative example 1 uses the blotting processdisclosed in JP-A-63-45813. The comparative example 2 uses the blottingprocess in which the electronic component body 1 is moved linearly withrespect to the surface plate 100. Regarding the blotting processes inthe comparative examples 1 and 2, the difference of the conductive pastelayer 4 a in TOP film thickness (film thickness T1 in FIG. 2) occurringdue to the difference in length between the electronic component bodies1 a and 1 b was as large as 7 to 8 μm. On the other hand, in the presentembodiment, the difference in TOP film thickness of the conductive pastelayer 4 a was reduced to 2 μm. From this, the uniformization effect ofthe thickness T1 (FIG. 2) of the conductive paste layer 4A by theblotting process illustrated in FIGS. 5 and 12 is understood.

Further, the blotting process illustrated in FIGS. 5B and 12 may notnecessarily use the carrier plate 20 used in the coating processillustrated in FIG. 10, because the blotting process does not requirethe elastic deformation of the carrier plate 20. Further, in the coatingprocess illustrated in FIG. 10 and in the blotting process illustratedin FIGS. 5B and 12, it is unnecessary to use the same surface plate 100.A first surface plate may be used in the coating process illustrated inFIG. 10, and a second surface plate may be used in the blotting processillustrated in FIGS. 5B and 12.

In the blotting process according to the third embodiment of thedisclosure, the height changing process and the position changingprocess may not necessarily be performed simultaneously. In short, theposition changing process should be performed at positions different inthe distance between the end face 2A of the electronic component body 1and the surface of the surface plate 100. That is, at a plurality ofpositions different in height of the end face 2A of the electroniccomponent body 1, the electronic component body 1 and the surface plate100 may be relatively moved in the X-axis and/or Y-axis directions. Evenwhen the height changing process and the position changing process aresimultaneously performed, the movement is not limited to the spiralmotion. The electronic component body 1 and the surface plate 100 may berelative moved in the X-axis and/or Y-axis direction while causing arelative movement in the Y-axis direction.

Further, after the coating process illustrated in FIG. 10, the coatingstate of the conductive paste layer 4 formed on the end portion 2 ofrespective electronic component bodies 1 may be imaged with a camera,and if the coating length (length from the end face 2A) on the endportion 2 of the electronic component bodies 1 a and 1 b is not within apredetermined range, such an electronic component body 1 may be excludedas a defective component.

In the above-mentioned first to third embodiments, it may be useful toapply a conductive paste on the surface 101 of the surface plate 100before the blotting process to form a wet layer of the conductive pasteon the surface 101 of the surface plate 100. In this case, in theblotting process, extra conductive paste on the electronic componentbody 1, 1 a, or 1 b is brought into contact with the wet layer formed onthe surface of the surface plate. The extra conductive paste on theelectronic component body 1, 1 a, or 1 b is easily transferred to thewet layer of the same conductive paste rather than a dry surface of thesurface plate 100 mainly formed of metal. Alternatively, when theviscosity of the conductive paste is low, the amount of conductive pastetransferred to the wet layer can be reduced.

What is claimed is:
 1. An electronic component manufacturing method comprising: blotting by bringing a conductive paste applied to an end portion including an end face of an electronic component body held by a jig into contact with a surface of a surface plate, thereby transferring extra conductive paste to the surface plate, the blotting including simultaneous performance of: distance changing of changing a distance between the end face of the electronic component body and the surface of the surface plate, and position changing of changing a two-dimensional position where the end face of the electronic component body is projected on the surface of the surface plate in such a manner that the movement direction of the two-dimensional position successively varies on the surface of the surface plate, wherein in the position changing, the movement locus of the two-dimensional position draws a loop, and in the blotting, the electronic component body is spirally moved relative to the surface of the surface plate.
 2. The electronic component manufacturing method according to claim 1, wherein prior to the blotting, the conductive paste is applied to the surface of the surface plate to form a wet layer on the surface of the surface plate.
 3. The electronic component manufacturing method according to claim 1, wherein the distance changing extends the distance between the end face of the electronic component body and the surface of the surface plate.
 4. The electronic component manufacturing method according to claim 1, wherein the distance changing shortens the distance between the end face of the electronic component body and the surface of the surface plate.
 5. The electronic component manufacturing method according to claim 1, wherein the distance changing extends the distance between the end face of the electronic component body and the surface of the surface plate, after shortening the distance between the end face of the electronic component body and the surface of the surface plate.
 6. The electronic component manufacturing method according to claim 1, wherein the blotting is performed with a plurality of electronic component bodies being held by the jig.
 7. The electronic component manufacturing method according to claim 4, further comprising coating by applying the conductive paste to the end portion of each of the plurality of electronic component bodies held by the jig by bringing the end portion including the end face of each of the plurality of electronic component bodies into contact with a dip layer of the conductive paste formed on the surface of the surface plate, wherein the coating includes bringing the end face of each of the plurality of electronic component bodies into contact with the surface of the surface plate by causing relative movement of the jig and the surface plate, the jig elastically holding the plurality of electronic component bodies so as to be movable in a direction perpendicular to the surface of the surface plate. 